Across
1
The number representing nothing
4
Result of raising a number to an exponent
5
Sum divided by count
11
Part of a circle's circumference
12
Rectangle with four equal sides
13
Single numeral from 0 to 9
Down
2
Longest side of a right triangle
3
Mathematical statement of equality
6
System of ordered marks for measuring
7
Difference between highest and lowest values
8
Number greater than zero
9
Value that does not change
10
Steepness of a line